Home made BlinkM units

[Stephen] wrote in to show us this fun LED wall he constructed in his house. He says he was inspired by this project, but found the cost of the BlinkM units from sparkfun to be out of his price range. He really liked how they worked though, so he downloaded the schematic and firmware and built his own. He was able to fabricate 130 of his own for roughly 250 euros as opposed to the 1,452 euro price tag his sparkfun shopping cart had. That’s not a bad deal at all if you’re willing to invest the time in making your own PCBs and assembling the units. You can follow along on his site to see the entire construction process, as well as some pictures of his glass wall in action. The videos, however, aren’t loading for us. Great job [Stephen]!

I think what you are talking about is a chip per unit. This is used to parse I2C data from a single serial connection. Each unit has an address allowing you to control them all from a single Uc. This is done by assigning a value to the specific address of the unit you want to control.

The uC on the individual “BlinkM” is also used to control the PWM output which controls the color of the attached RGB LED.

IMHO this is very exciting.
as a mech. engineer I always liked blinkms but could never afford to order a useful quantity.
I’m going to do an electronics workshop for kids, each kid will build a few units, then we connect them together to get a “matrix”.

Where did you get the idea that the premade cost is 1,452 euros? He says right on the page: “US $1452″. He also spent more than just the 250 euros at Mouser. Fortunately, he even totaled it up for you: 361 euros!

Do you even read the page before posting? How do you know it isn’t Goatse halfway down?

OK, so after reading the comments, I removed the background for readability and replaced the WMP with links so the page will load faster and the users can choose if they want to see the videos or not.
Enjoy.
Stephen

I’ve ordered the LEDs from bliptronics. both the flat rgb strip and the pixels. They are both very impressive. Problem is, min 10 days to receive. Found then fir the same overall cost from adafruit and they are based in NY.

@ the Creator, exacly thats what I mean. But a TLC 5941 has 16 PWM outputs for LEDs programmed with SPI Bus. If you hang 3 of these chips on one µC you can control 16 RGB LEDs with one µC. If you want you can use IIC for the µC and thus reduce cost by having the same functionality. I use PIC Micros and JAL v2 as programming language, and have made an ambient Light for my livigroom with those (only 4 RGB LED Stripes) one 18f23k20 one TLC5941 and a serial-bluetooth (cheap chinese)adapter for controlling it with my old windows mobile 2003 ppc. There are some better PWM controllers with lots more outputs on the market, but they come with SMD Case and i like old fashioned through hole components.

tlc5940’s can be used for led matrix, as well as addressing individual leds. It’s nice that he managed to slash the blinkM pricing and of course these can be configured and addressed in whatever shape you like.

I think this is really cool. I like the idea and most of the implementation. Why did he use an Arduino board in the final design? There was all the effort that went into the design of the individual led boards. Why is the arduino board still in the box. I don’t care if he is using the arduino bootloader, that is fine. I just don’t like the fact that he has a prototyping board in a finalized project.

Half of his costs go to the ATTiny85, I’m pretty sure the software in the ATTiny isn’t that complex for a 3 color PWM LED. So going with a smaller uC would save you a bit more (ATTiny25 seems to be atleast 30% cheaper, and an ATTiny13 is even cheaper then that)

I popped in here to say that I agree with the comment left by “The Cageybee”

While the schematic for BlinkM is open and the firmware is available for download, it is my opinion that it would not be lawful to use the BlinkM firmware on alternative devices. Tod from ThingM would probably have the authoritative answer on that, but the short story is that Philips has some patents on controlling RGB LED lighting over I2C that ThingM have licensed in order to sell the BlinkM and all the associated devices. I cannot imagine that this license extends ThingM the ability to offer the firmware for use on unofficial devices.

That is the reason when I built a project that uses alternative hardware I chose to start with the CYZ_RGB firmware. At the time, it was not particularly mature. Since that time I have fixed a number of bugs and added a few great features such as sRGB fade curves and internal 16 bit PWM. It’s still missing some of the features of BlinkM such as full scripting, but it’s quite a bit more useful for general lighting projects due to the better color accuracy available in CYZ_RGB. I would encourage people to try it out on BlinkM or their own hardware and send me your feedback. It’s not a very active project, but I do try to be responsive to folks.

I should mention that due to the patent situation, anyone using CYZ_RGB (at least in the US) should be careful to ensure they are in compliance. My own use is limited to personal noncommercial projects, but others should be aware of the potential issues.

Replying to an old one, but what IS the purpose of the 2 NXP I2C level shifters?

There are 2… so it’s easy to attribute them to each Arduino or each “block”. Stephen hints at a firmware limitation and the need to level shift. But shift levels how.. aren’t the Arduino and BlinkM nodes both running at the same 5 volts?

Or are the I2C shifters serving some other purpose, like acting as a router/repeater, or to simplify wiring?